Sliding door spring



Oct. 2, 1934. G. P. ANsTlss 1,975,627

SLIDING DOOR SPRING Filed Oct. 51. 1950 2 Sheets-Sheet 1 Oct. 2, 1 3 G. P. ANSTISS SLIDING noon SPRING Filed Oct. 51 1930 2 Sheets-Sheet 2 I11) ant;

or n(ey s i 11/1/74 .INILE i 9 4f .I

'IIIIIIIIIIIIIII site end of the machine.

35 strength to open one Patented Oct. 2, 1934 PATENT OFFICE.

7 1,925,627 SLIDING" noon SPRING George P. -'Anstiss, River Forest, Ill., assignor to G. S. Blakeslee & 00., Cicero, III., a corporation of Illinois Application was 31, 1930, Serial No. 492,471

I 8 Claims. (01. 2ss-5s This invention relates to a door spring for sliding doors.

Cabinets built to encase devices such as a dish washing machine, for example, are-frequently 5 provided with a plurality of doors which are opened in pairs in orderto give access to the mechanism in the cabinet, this arrangement being employed so that as one article is pushed into the machine through one of the open doors a corresponding article is thereby pushed out of .it through the other of the open doors Thus,

in a dishwasher when a tray of dirty dishes is inserted in one end of the machine a similar tray of washed dishes is expelled from the'oppo- The doors by which a cabinet of this kind is closed are usually sliding doors, and it has been necessary heretofore, in so far as 1 am aware, to manually operate both of the doors in order to permit the entrance 2 into and simultaneous discharge from the machine of a tray of dishes or the like.

My presentinvention has for its principal. object the provision of a simple arrangement whereby one of the pair of doors of a cabinet of this kind will be automatically open responsive to a manual opening of the other door of the pair, the mechanism also being effective to close both doors by manually closing one of them.

In the preferred embodiment of my invention, I provide a spring controlled Windlass on which is wrapped a pair of cables which extend over suitable pulleys and are attached to the doors'that are to be operated. The spring by which this Windlass is actuated is of sufficient of thepair of doors, but not of sufiicient strength to open both of them. Therefore, when one of the doors is manually opened and its weight thereby taken off the Windlass, the spring rotates that Windlass to open the other door of the pair. When the doors are to be closed, a slight pressure exerted on one of them will enable their weight to overcome the tension of the springa'nd to unwind the windlass so that the doors may be moved into their closed position. g

If the cabinet upon which this door closing device is installed houses a dish washing machine, for example, it is imperative'that the doors be tightly closed so that the spray of steam and water employed in the washing of the articles in the machine will be confined within the cabinet and not permitted to escape therefrom, In orderto insure that the door operating mechanism will in' no Way hinder the perfect closing of the door, I have provided an arrangement whereby the mechanical leverage of the force exerted on the Windlass by the door is increased during the last part of the movement of the door .on closing, so that the weight of the doors predominates over the tension of the spring to permit the doors to move positively into their closed position.

Now to acquaint those skilled in the art with the teachings of my invention, reference is made to the accompanying drawings in which a preferred embodiment of it is shown by way of eX- ample, and in which:

Figure 1 is a perspective view of the invention applied to the doors of a cabinet;

' Figure 2 is a cross sectional view through the i 1.-

door closing mechanism;

Figure 3 is a cross sectional view of the door closing mechanism taken along the line 33 of Figure 2 looking in the direction of the arrows;

Figure 4 is a fragmentary elevational view of f the cabinet showing a slightly modified form of my invention; and

Figure 5 is a fragmentary elevational view in section showing a modified embodiment of my invention.

Referring now to the drawings in more detail, the cabinet 1 shown by way of example is a rectangular structure supported on legs 2, 3 and 4 and provided with doors 5 and 6, which are arranged to be simultaneously opened.

The door operating mechanism consists of a grooved Windlass drum '7 ro-tatably supported upon a vertically disposed shaft 8 which is attached to the cover'member 9 of the cabinet in any preferred manner such as by the bracket 18 which is riveted to the member 9 as shown at 11. Within the drum '7 is an annular chamber 12 which is closed at one end by the web 13. The hub 14 by which the drum is held upon the shaft 8 is disposed concentrically in this chamber 12.

A coil spring 15 is disposed in this chamber with one of its ends attached to the wall member 16 of the chamber in any preferred manner such as by the screw 17, and the opposite end of this spring is formed in a loop 18 disposed adjacent to the hub 14 of the drum.

The open end of the chamber 12 is closed by a plate 19 which is supported on the shaft 8 by an integral hub 20 and held against rotation thereonby a wing bolt 21 threaded into the hub 20 and engaging the surface of the shaft 8. A pin 22 is threaded into the plate 19 and projected through the loop 18 in the spring to thereby hold that end of the spring 15 fixed with respect to the shaft 8 and the cabinet 1. The upper end of the shaft 8 is threaded and provided with a nut 23 which bears upon the washer 24 disposed on the upper end of the hub 20 to retain the plate 19 upon the shaft independently of the wing bolt 21.

The plate 19 is provided with a pair of handles 25 and 26 by which it may be rotated with respect to the shaft 3, after the wing bolt 21 has been loosened, in order to wind up the spring 15,and thereby place a certain amount of tension in it.

A plurality of pulleys 3G, 31 and 32 are attached to the top member 9 of the cabinet in any preferred manner such as by riveting. Cables 33 and 34 are attached to the handles 35 and 36 of the doors 5 and 6, respectively, and threaded over the pulleys 30 and 31 and extended to the groove 3? formed in the outer surface of the drum 7 to receive them. As will be seen in Figure 3, the cable 33 encircles the drum 7 in the groove 37 and is attached to the pin 38 which is in turn rigidly attached to the drum near its outer periphery. The cable 34 is similarly attached to the drum 7. When the doors are fully closed, the respective cables occupy the dotted line position of Figure 3, so that the length of the effective lever arm of the drum is increased relative to the length of the effective lever arm of the drum when the cable is wound thereon.

With the cables 33 and 34 attached to the drum and doors in the manner shown, the spring 15 is tensioned by the rotation of the plate 19 until it has sufiicient power to lift one, but not both, of the doors 5 and 6 when the doors are in full closed position. Therefore, when one of the doors, say 5 for example, is raised by a person taking hold of the door handle 35 and elevating it, the weight of the door 5 is removed from the cable 33 and in turn from the drum 7; so that the spring 15 is able to rotate the drum 7 and wind the cables 33 34- onto it in the groove 37. As the cable 34 is wound up on the drum, door 6 is raised in the obvious manner, and after the drum has turned sufficiently to wind the cables thereon to such an extent as to shorten the effective lever arm of the drum, the spring becomes eifective to raise both of the doors so as to complete opening thereof.

It will be noted that when the door is completely closed the cable 33 projects tangentially from the pin 38 in the manner shown in dotted line in Figure 3. Since the pin 33 is farther from the center line of the drum than the bottom of the groove 37, the weight of the door acting upon the other end of the cable has its maximum leverage and therefore a maximum spring tension is required to rotate the drum and elevate the door. By properly tensioning the spring 15 it can be made to have suiiicient power to move the door out of its closed position against the maximum leverage afforded by the engagement of the pin 38 with the drum '7.

The tension of spring 15 is made sufficient to hold both the doors 5 and 6 in their open posi tion after they have been opened in the manner described. With this adjustment of the spring it will be necessary to exert a slight downward pressure upon the handle of one of the doors in order to overcome the tension of the spring 15 by pulling the drum '7 around against that tension. With the drum thus put in motion by manually moving one of the doors, the cable of the other door will be unwrapped from the drum and that door will therefore descend to its closed position under the action of gravity.

Shortly before the doors 5 and 6 reach their lowermost or closed positions their cables 33 and 34, respectively, are pulled out of the bottom of the groove 3''! by the movement of the pin 38 toward the position shown in dotted lines in Figure 3. The line of pull of the cable is thereby moved outward, and the weight of the doors and downward pull of the operator are thereby given an advantage over the'tension of the spring 15 so that the speed of the doors increases and they seat themselves firmly in their closed positions.

As shown, the pin 38 is attached to the drum 7 near its outer periphery, and by adjusting the position of'this pin inwardly or outwardly the amount of advantage given to the doors can be regulated to meet requirements. Preferably this adjustment is made so that the doors seat themselves positively but do not bang in so doing. The adjustment, when once set, is permanent so long as the weight of the doors remains unchanged.

As shown in Figure 1, the pulleys 30 and 31 are disposed outside of the cabinet and the cables 33 and34 are also disposed outside of the cabinet, this arrangement being necessary when the cabinet houses an oven or the like. In certain instances it may be advantageous to have the cables 33 and 34 disposed within the cabinet, and in Figure 4 I have shown a slightly modified form of cabinet in which the pulley 40, which is similar to the pulleys 30 and 31, is set inwardly of the edge of the top plate 9 of the cabinet and that plate is provided with a hole 41 through which the cable 42 is projected and attached to the interior side of the door 43 by a screw eye 44. The spring driven Windlass, indicated generally at 45, is identical with the Windlass hereinbefore explained. By this arrangement the front space of the cabinet adjacent'the door 43 is unobstructed by a cable, which is obviously advantageous in many instances.

In, certain other instances it is disadvantageous to have either the Windlass or the pulleys and cables disposed upon the top of the cabinet, and I have therefore in Figure 5 illustrated an embodiment of my invention which permits disposing these devices in the cabinet.

In this embodiment of the invention, the windlass spring is disposed in a casing 50 which consists of a bottom plate 51 attachedv to the upper surface of the top member 52 and containing a hub 53 which projects through a central opening 54 in that surface. The cover 55 of the spring case 50 forms, with this plate 51, a chamber 56 in which the spring 57 is disposed. A shaft 58 is projected through a hub 59 in the cover 55 and 1 a drum 60 which is constructed similarly to the drum hereinbefore explained, and which is provided with a hub 61 embracing the lower end of the shaft 58 and containing a pin 62 by which the hub 61 is fixed with respect to the shaft. The

shaft is supported in the hubs 53 and'59 by a nut 63 threaded onto the threaded end 64 of the shaft drum 60 by a pin similar to the pin 38 of Figure 3. The drum GO is provided witha gr'oove '67 into which the cable 72 is thr'eadedas before.

The spring 57 is attached to the shaft 58 by a pin 76 and to the casing by apin T7, so that as the drum is rotated tension-is stored up in the spring 5'7. 'As'shown, the spring 57 1stenionedby-turningthe casing 55 with respect to the piate 51 in quarter revolution steps. With the size of spring properly chosen, with respect to the weight of the doors, the desired mode of operation of the device can be easily secured by this adjustment and it is not necessary to frequently readjust the tension of spring 57 after it has once been properly set.

The cabinets shown in Figures 4 and 5 are provided with a pair of doors and a pair of cables, both of which are attached to the drum of the Windlass in the hereinbefore explained manner so that when one of the doors is manually moved to open or closed position the other door will be moved in a corresponding direction by the automatic action of the Windlass.

The embodiments of my invention illustrated in Figures 4 and 5 lend themselves particularly well to use in cabinets in which the doors are mounted outside of the frame, and when opened extend above the top surface of the cabinet. The cabinets fragmentarily shown in these figures, 4 and 5, are of this type, and are particularly advantageous for use as washing machine cabinets since the water that collects on the undersurface of the top plate 9 and inside surface of the apron 79 runs down the inside surface of the door 43 and returns to the cabinet. The outside surface of the door obviously is not moistened by this water.

The embodiment shown in Figure 5 is particularly advantageous for use in washing machines since the cables are also wholly contained within the cabinet, and notwithstanding that they are sprayed with water, that water cannot escape from the cabinet and the top surface as well as the outside of the doors is therefore maintained dry and tidy.

In Figure 1 I have shown an extra pulley 32 indicating that the door 6 may be disposed opposite to the door 5 if it is desired to do so. In fact, the doors may be located on any two of the four sides of the cabinet and operated in pairs by the spring riven Windlass of my invention, not only in the form shown in Figure l but also in the forms shown in Figures 4 and 5.

While I have illustrated my invention by showing a preferred embodiment of it, I have done so by way of example only and the invention is not to be limited except by the scope of the appended claims.

What is claimed is:

1. The combination with a cabinet of a pair of equal weight doors therefor, a Windlass pivotally mounted on the cabinet, cables connecting said Windlass to said doors, and means for driving said Windlass, said means being capable of lifting the weight of said doors through said windless, when the doors are in lowered position, and capable of completing the opening of the doors, when they have been opened to a predetermined extent, and of holding the doors open.

2. A door lifting mechanism comprising a shaft, a spring connected thereto, a drum keyed to the shaft and having grooves for receiving cables, a pair of cables each having one end connected to a door, and means for attaching the free ends of said cables to said drum, said means placing the points of attachment of the cables outside said grooves to'thereby alter the lever 'arms'of said cables on said spring as the cables are wound on the drum.

' 3."Ihe combination with a cabinet having .a plurality of door means, of an operating mechanism comprising a plate disposed outside of said cabinet, a boss on said plate extending into the cabinet, a housing rigidly attached to said plate, a shaft journaled in said housing and boss and extending into said cabinet, a spring attached to said housing and shaft, a drum keyed to said shaft, said drum containing peripheral grooves corresponding in number to the number of said door means, a cable disposed in each of said grooves and attached to said drum and extending to a door means, and means for securing said cables to their respective door means, said cables revolving the drum to tension said spring as the door means are moved in one direction, and said spring operating said drum responsive to a manual operation of one door means in a reverse direction to automatically move the other door means.

4. In combination in a device of the character described, a pair of doors, a Windlass, cables connected to the respective doors and windable onto and off of the windlass, yielding means urging the Windlass in cable winding direction for opening the doors, and connections between the cables and the Windlass disposed to increase the length of the effective lever arm of the Windlass when the doors are closed relative to the length of the effective lever arm of the Windlass when the cables are wound onto the Windlass, the yielding means being ineffective to open the doors when they are closed and effective to complete opening of the doors, when they have been opened to a predetermined extent and the cables are wound upon the Windlass, and to hold the doors open.

5. In combination in a device of the character described, a pair of doors, a Windlass, cables connected to the respective doors and windable onto and off of the Windlass, yielding means urging the Windlass in cable winding direction for opening the doors, and means rendering the yielding means ineffective to open the doors when they are closed and effective to complete opening of the doors, when they have been opened to a predetermined extent, and to hold the doors in open position.

6. In combination, a cabinet provided at two 1 sides with slidably mounted doors, a shaft, a member rotatable thereabout and having 2. depending offset pin, a spring coiled about the shaft and anchored at one end to said pin, means for holding said member in fixed position with respect to said shaft, a drum rotatably mounted on the shaft, two cables windable onto and off of the drum and connected to the respective doors, and means connecting the other end of the spring to the drum for tensioning said spring by rotation of the drum in cable unwinding direction.

'7. In combination, in a device of the class described having a pair of vertically slidable doors, a fixed shaft, a Windlass mounted on said shaft rotatable thereabout, a spring coiled about said shaft, a member mounted on and adjustable about said shaft independently of the Windlass, said spring being anchored at one end to said Windlass and at the other end to said member, and a pair of cables connected to said doors and wound Li.

about said Windlass in proper direction for turning it in spring tensioning direction when the doors are moved in closing direction.

8. In combination, in a device of the class described, a pair of opposed vertical sliding doors,

about said shaft, offset depending means carried by said member for anchoring the other end of said spring to said tensioning member, and a pair of cables connected to said doors and wound about said Windlass in proper direction for tensioning said spring upon closing movement of said doors.

GEORGE P. ANS'IISS. 

